naturally regenerated over a short time scale
directly from the sun (thermal)
indirectly from the sun (wind, hydropower)
from other natural movements and mechanisms of
the environment (geothermal, tidal energy).
1.When its source
cannot run out (like
the sun) or can easily
be replaced (like
2. When their
sources are carbon
neutral. That means
they do not produce
(such as other green
3.When they do
not pollute the
(air, land or
1) WIND ENERGY
2) SOLAR ENERGY
a) Small hydro
b) OCEAN Thermal
d) WAVE action energy
5) GEOTHERMAL ENERGY
• The largest wind turbine in the world, located in Hawaii,
stands 20 stories tall and has blades the length of a
• An average wind speed of 14 miles per hour is needed to
convert wind energy into electricity.
• The first power-generating turbine was constructed in
Ohio during the late 1800's and was used to charge
• Wind energy is the fastest growing segment of all
renewable energy sources.
•WIND TURBINES REQUIRE NO FUEL
•WIND TURBINES DO NOT PRODUCE
ANY WASTES, GREENHOUSE GASES,
TOXINS OR BY-PRODUCT THAT CAN
HARM THE ENVIRONMENT.
CAN BE USED FOR
A good method of
supplying energy to
•Wind farms can be built offshore
It is considered 'renewable energy' because...
• The technology used to convert the sun's power into
electricity does not produce smoke (carbon dioxide and
other air pollutants).
• Tapping the sun's energy does not usually destroy the
Largest solar thermal power plant generating facility in
the world: Solar Energy Generating Systems (SEGS) in
California, with the combined capacity from three
separate locations at 354 megawatts.
•Solar energy will
last forever whereas
it is estimated that
the world’s oil
reserves will last for
30 to 40 years.
•Solar cells make
absolutely no noise at all.
On the other hand, the
giant machines utilized for
pumping oil are extremely
noisy and therefore very
•Very little maintenance
is needed to keep solar
cells running. There are
no moving parts in a
solar cell which makes
it impossible to really
•Solar energy can
be used in remote
areas where it is
too expensive to
•Solar energy does not
cause pollution. However,
solar collectors and other
associated equipment /
manufactured in factories
that in turn cause some
• Biomass is used to make biofuels.
• Biomass is biological material derived from
living, or recently living organisms.
• Biofuels are liquid fuels which have been
derived from other materials such as waste
plant and animal matter.
Waste residues will always
exist – in terms of scrap wood,
mill residuals and forest
Properly managed forests will
always have more trees, and we
will always have crops and the
residual biological matter from
•It makes use
•It will lead to
less demand on
•Hydropower is renewable energy source that doesn't
cause global warming because it doesn't releases
dangerous greenhouse gases.
•China is the largest producer of hydroelectricity,
followed by Canada, Brazil, and the United States
(Source: Energy Information Administration).
•Hydropower is the most important and widely-used
renewable source of energy.
To meet any changes in demand for
electricity, hydroelectricity generators can
be stopped and started in minutes.
A fossil fuel power station can take up to eight
hours to shut down or restart
A nuclear power station can take up to several
Operation and maintenance costs for
hydroelectricity plants are much lower than
for thermal electricity power plants.
Breakdowns are few because their mechanical
design is relatively simple, and no excess heat
is generated during operations.
No waste by-
Geothermal energy is the heat from the
Geothermal energy is called a renewable
energy source because the water is
replenished by rainfall, and the heat is
continuously produced by the earth.
The Pohutu Geyser in New Zealand erupts with a natural blast
of the Earth's interior heat.
• Because geothermal energy is energy in and of itself,
no outside sources of fuel are needed to keep the
power houses running.
• The supply of this renewable energy is constant, as
well as without limits since the earth is never going to
stop producing heat energy and in theory, energy is
abundant enough to supply all the needs of all
First country in the world to set up a ministry of
non conventional resources, in early 1980s
The renewable power installed capacity forms
12% of the total installed capacity as on Oct 2012
Actual electricity generation from renewable
energy sources equals 49.04 billion units.
RE generation from Small Hydro power
is 3421 MW, i.e 13% of RE
With 17,875 MW of generation, wind
continues to account for 70% of the
installed RE capacity
of India as of 2012
Wave energy Plant at Vizhinjam near
Trivandrum in India
Compressed natural gas
Renewable Energy Sources and Emerging Technologies
By D.P Kothari, K.C Singal, Rakesh Ranjan.
Renewable Energy : A common sense energy plan by Brad
Solar Energy: Renewable Energy and the Environment by
Robert Foster, Majid Ghassemi, Alma Cota.
Power Ahead with Renewables: Leaders And Laggards,
Report by Greenpeace India